I recently put new tires on my truck(LT235/85R16E) Today I checked to preasure and they are inflated to 65psi. The side wall of the tire says 75psi max. What amount of preasure is ideal for these tires and my truck?

95 PSD CC LB 4x4

 

Most people seems to like 60-65 psi. If the ride is too stiff for you, you might deflate to around 60 psi.

If you are hauling heavy, you probably want to be closer to the 75 psi max.

 

I run 60psi in my truck all the time , I get a decent ride and still enough to haul a load.

 

If you vary the tire pressure (loaded vs unloaded), doe sthe alignment change?

 

The max psi stated on the tire isn't necessarily the correct pressure for your truck. The max psi is required if you are loading the tire to full capacity, which should rarely happen because you normally hit the axle rating before you reach the tire load rating. If you are running the stock tire size, then the door sticker would be the best place to start. My door sticker says 50 psi front and 55 psi rear. I actually run with 65 psi front and 60 psi rear when unloaded, and 70 psi front and 80 psi rear when loaded (1900 lbs pin box weight). I've monitored the wear patterns on my tires to arrive at these pressure levels. At the door sticker pressures, I noticed "cupping" wear patterns (more wear on the shoulders and light in the center). At higher pressures I noticed "crowning", more wear in the center and none on the shoulders. You can actually see where the wear marks don't quite reach the edges of the tread blocks. Most tire brands have little wear marks on the outside edges of the tread patterns, your tires should wear all the way up to these marks.

All 4 of my trailer tires are set at 80 psi, the wear patterns are looking good so far.

Of course, all these pressures are "cold" readings. I'm just not sure what "cold" is, so I always check my pressures in the morning, after the truck has been parked overnight. But I wonder if my tire pressures would read lower during 30 degree mornings and higher at 70 degree mornings? If "cold" is a baseline, than shouldn't it be taken at a certain temperature? Maybe I'm taking tire pressure too seriously, but I see and hear about too many serious highway accidents because of truck/trailer tire failures.

 

my doorjamb says 45 front, 70 rear. The tires LT265/75R16 say 80 psi max. I usually run 70 front, 75 rear. This works well for towing a trailer in the summer, in the winter I load the bed with 1000 lb of sand, and tow minimally. The ride is a little stiffer, but the tire wear is even and is not excessive (it will be if your tires are under-inflated).
I loaded my folks' truck with cordwood 2 weeks ago and the tires were quite squashed. The fool that put them on only put 35-40 psi in the rears. At 70 psi the tires were still slightly squished & the suspension was just touching the helper springs, but te tires no longer bulged out at the sidewall like they had when under-inflated.

 

Empty, I run 55 front & 45 rear. This seems to keep the tires round enough to reduce wear, and not ride near as rough. Washboard gravel roads are hell with 65 lbs. and little weight in the bed.

 

I ran 60 up front and 80 in the rear all the time, then I bought my new 285/75 A/T's at 40K. The tire guy asked my pressures and recommended what I run now. When unloaded, i run 55 up front and 45 in the rear. When towing i run 55-75 in the rear depending on my load. My tires wear evenly, and the truck handles great.

In the sand on the beach, i run 30/30 unloaded or 22/22 pullin a trailer.

The sticker on my gas cover says 80 rear and 55 front. I guess it all matters on what your doin and where you're doin it!

 

CGL - do you carry a compressor on board to let you change your pressures?

 

I've always had my trie pressure up there also. And have had good luck with wear, etc. Even with Firestones.

I either have a snowplow on it or tow a boat, or rubbish, and now a camper in the bed.

Some guys blow tires and they never state why, but I bet it's because they don't keep and eye on pressure and keep it up.

Speed will factor in with high temps coupled with low pressure, with loads on them.

I leave em up the harder ride between hauling doesn't bother me.

I've run E ply's of all kinds and never had a blow out very little flats, if any for 25 years.

Capt.

 

I'm using a gas powered compresser most of the time. I am looking into a system right now, and will post back when I get more info.